Acute ischemic stroke is one of the major sources of morbidity and mortality in the industrialized countries. In the USA, approximately 795,000 patients experience a stroke every year. Intravenously administered tissue plasminogen activator (IV tPA) has been shown to improve patient outcome. However, the time window for treatment and the recanalization rate of this approach are limited, and the application of thrombolytic drugs increases the risk of symptomatic intracranial hemorrhage. The success of recanalization, furthermore, depends on the occlusion site.
Mechanical recanalization techniques, i.e., mechanical thrombectomy devices can accelerate the process of recanalization, increase the recanalization rate, and even expand the window of opportunity. Some in-use mechanical thrombectomy devices generally fall into three categories: 1) devices including a filter trap designed and built to collect and remove embolus; 2) a cork-screwed guidewire like device to retrieve embolus; and 3) a stent like device connected to a delivery wire to retrieve embolus.
Some common concerns of physicians who practice angioplasty include: concern that the thrombectomy device may capture an embolus, only to lose hold of it and accidentally deposit it in another area of the neurovasculature; concern that the device may not be able to capture a ‘break-off’ piece of the embolus, which may migrate further into the neurovasculature; concern that the relatively large device may prevent it from accessing and treating clots in small-diameter vessels; and concern that the devices usually require adhesive joining or bonding between the delivery system and the treatment device. In the latter case, in some instances a concern is that the adhesive bonding may fail, presenting the possibility that the pieces may separate, presenting a serious complication in the procedure.